The Aswan High Dam, built in the 1960s, created major change in one of the world’s largest and most famous rivers. The dam stopped the annual flooding that pro- vided new fertile soil each year, the basis for agriculture in ancient Egypt, the world’s longest existing civilization. The decrease in water flow below the dam also changed the eastern Mediterranean Sea. Prior to the dam construction, Mediterranean water was less salty than regular sea water because its waters mixed with freshwater from the Nile. Without the Nile outflow, the eastern part of the Mediterranean became saltier, affecting fish and fisheries. The lake is some 550 km long and 35 km across at its widest point, which is near the Tropic of Cancer. It covers a total surface area of 5,250 km² and has a storage capacity of some 157 km³ of water. The lake was created as a result of the construction of the Aswan High Dam across the waters of the Nile between 1958 and 1971.